Adrenal autoantibodies bind to adrenal subcellular fractions enriched in cytochrome-c reductase and 5'-nucleotidase.
A quantitative assay for human adrenal autoantibodies has been developed to aid in the detection and isolation of human adrenal antigens. To define the subcellular location(s) of the antigen(s) capable of binding with these antibodies, we have quantitated both antibody binding to various adrenal subcellular fractions and the adrenal autoantibody binding inhibition caused by each subcellular fraction. To further define the subcellular location of the autoantibody binding, each fraction was assayed for organelle-specific marker enzyme activities. Enzyme activities were correlated to adrenal autoantibody binding to each fraction by linear regression. Of the materials tested, both antibody binding and inhibition of binding were most highly correlated with adrenal subcellular fractions enriched with cytochrome-c reductase and 5'-nucleotidase (r = 0.98; P less than 0.05). Thus, our data support the localization of adrenal autoantigen(s) in the microsomes, plasma membrane, or both.
Bright
G M
GM
Division of Endocrinology, Medical University of South Carolina, Charleston 29425.
Singh
I
I
D015720:5'-Nucleotidase / Q000302:isolation & purification*; D000311:Adrenal Glands / Q000201:enzymology / Q000276:immunology*; D000937:Antigen-Antibody Reactions; D000941:Antigens / Q000302:isolation & purification; D001323:Autoantibodies / Q000302:isolation & purification*; D001666:Binding Sites, Antibody; D002462:Cell Membrane / Q000201:enzymology / Q000276:immunology; D003579:Cytochrome Reductases / Q000302:isolation & purification*; D006801:Humans; D008861:Microsomes / Q000201:enzymology / Q000276:immunology; D009245:NADH Dehydrogenase / Q000302:isolation & purification*; D013050:Spectrometry, Fluorescence; D013347:Subcellular Fractions / Q000201:enzymology / Q000276:immunology
D000941:Antigens; D001323:Autoantibodies; D003579:Cytochrome Reductases; D009245:NADH Dehydrogenase; D015720:5'-Nucleotidase